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        // function fn1(){
        //     function fn2(){
        //         function fn3(){
        //             a = 10
        //         }
        //         fn3();
        //         // console.log(a);
        //     }
        //     fn2();
        //     console.log(a);
        // }
        // fn1();
        // console.log(a);



        function fn1(){
            function fn2(){
             var    fn3=()=>a = 10
                   
                
                fn3();
                console.log(a);
            }
            fn2();
            console.log(a);
        }
        fn1();
        console.log(a);
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